<template>
	<!-- 解决页面加载时价格名称显示undefined，因为在数据请求回来之前，data中的goods_info的值为{}，
	所以我们应该用v-if来判断goods_info.goods.name是否存在，从而控制页面的显示与隐藏 -->
	<view v-if="goods_info.goods_name" class="goods-detail-container">
		<swiper :indicator-dots="true" :autoplay="true" :interval="2000" :duration="1000">
			<swiper-item v-for="(item,i) in goods_info.pics" :key="i">
				<image :src="item.pics_big" @click="preview(i)"></image>
			</swiper-item>
		</swiper>
		<!-- 商品信息区域 -->
		<view class="goods-info-box">
			<!-- 商品价格 -->
			<view class="price">
				￥{{goods_info.goods_price}}
			</view>
			<!-- 信息主体区域 -->
			<view class="goods-info-body">
				<!-- 商品名称 -->
				<view class="goods-name">
					{{goods_info.goods_name}}
				</view>
				<!-- 收藏 -->
				<view class="favi">
					<uni-icons type="star" size="18" color="gray"></uni-icons>
					<text>收藏</text>
				</view>
			</view>
			<view class="yunfei">
				快递:包邮
			</view>
			<!-- 商品详情信息 -->
		</view>
		<rich-text :nodes="goods_info.goods_introduce"></rich-text>
		<!-- 底部商品导航按钮 -->
		<view class="goods_nav">
			<uni-goods-nav :fill="true" :options="options" :buttonGroup="buttonGroup" @click="onClick"
				@buttonClick="buttonClick"></uni-goods-nav>
		</view>
	</view>
</template>

<script>
	import {
		mapState,
		mapMutations,
		mapGetters
	} from 'vuex'

	export default {
		computed: {
			...mapState('m_cart', []),
			...mapGetters('m_cart', ['total'])
		},
		//监听器
		watch: {
			//动态显示购物车里物品的数量
			total: {
				handler(newVal) {
					//去options里找text为购物车的哪一项，如果找到了，就把options.info(角标数)的值改为newVal
					const findResult = this.options.find(x => x.text === '购物车')
					if (findResult) {
						findResult.info = newVal
					}
				},
				immediate: true
			}
		},
		data() {
			return {
				goods_info: {},
				// 引用了uni-app中的底部导航组件
				//options代表左侧按钮
				options: [{
					icon: 'shop',
					text: '店铺',
					infoBackgroundColor: '#FE6035',
					infoColor: "#f5f5f5"
				}, {
					icon: 'cart',
					text: '购物车',
					info: 0
				}],
				//buttonGroup代表右侧按钮
				buttonGroup: [{
						text: '加入购物车',
						backgroundColor: 'linear-gradient(90deg, #FFCD1E, #FF8A18)',
						color: '#fff'
					},
					{
						text: '立即购买',
						backgroundColor: 'linear-gradient(90deg, #FE6035, #EF1224)',
						color: '#fff'
					}
				],
			};
		},
		onLoad(options) {
			//获取商品ID
			const goods_id = options.goods_id
			//调用请求商品详情数据的方法
			this.getGoodsDetail(goods_id)
		},
		methods: {
			...mapMutations('m_cart', ['addToCart']),
			//商品详情数据的方法
			async getGoodsDetail(goods_id) {
				const {
					data: res
				} = await uni.$http.get('/api/public/v1/goods/detail', {
					goods_id
				})
				if (res.meta.status !== 200) return uni.$showMsg()
				//使用字符串的replace（）方法，为img标签添加行内的style样式，从而解决图片底部空白间隙的问题
				res.message.goods_introduce = res.message.goods_introduce.replace(/<img /g,
					'<img style="display:block;"').replace(/webp/g, 'jpg')
				//为data中的数据赋值
				this.goods_info = res.message
			},
			//实现轮播图的预览效果
			preview(i) {
				//调用uni.previewImage()方法预览图片
				uni.previewImage({
					//预览时，默认显示图片的索引
					current: i,
					//图片url地址的索引
					urls: this.goods_info.pics.map(x => x.pics_big)
				})
			},
			onClick(e) {
				if (e.content.text === '购物车') {
					uni.switchTab({
						url: '/pages/cart/cart'
					})
				}
			},
			//为添加购物车按钮绑定事件处理函数
			buttonClick(e) {
				if (e.content.text === '加入购物车') {
					//组织商品信息对象
					const goods = {
						goods_id: this.goods_info.goods_id,
						goods_name: this.goods_info.goods_name,
						goods_price: this.goods_info.goods_price,
						goods_count: 1,
						goods_small_logo: this.goods_info.goods_small_logo,
						goods_state: true,
					}
					//调用添加购物车方法
					this.addToCart(goods)
				}
			}
		}
	}
</script>

<style lang="scss">
	swiper {
		height: 750rpx;

		image {
			width: 100%;
			height: 100%;
		}
	}

	.goods-info-box {
		padding: 10px;
		padding-right: 0;

		.price {
			color: #C00000;
			font-size: 18px;
			margin: 10px 0;
		}

		.goods-info-body {
			display: flex;
			justify-content: space-between;

			.goods-name {
				font-size: 13px;
				margin-right: 10px;
			}

			.favi {
				width: 120px;
				font-size: 12px;
				display: flex;
				flex-direction: column;
				align-items: center;
				justify-content: center;
				border-left: 1px solid #999999;
				color: gray;
			}
		}

		.yunfei {
			font-size: 12px;
			color: gray;
			margin: 10px 0;
		}
	}

	//使底部导航栏固定在页面最下方
	.goods_nav {
		position: fixed;
		bottom: 0;
		left: 0;
		width: 100%;
	}

	.goods-detail-container {
		//给主体最底部加一个padding 使最下面的内容不会被覆盖
		padding-bottom: 50px;
	}
</style>
